Are we in a 6th mass extinction?

Scientists have documented five major mass extinction events in Earth's History, during which at least three-quarters of life went extinct. But with humans clearing habitats, exterminating species and changing the climate, are we now in a sixth mass extinction?

Many researchers claim the sixth mass extinction is underway, with one team describing "biological annihilation" and "mutilation of the tree of life" in their scientific studies. However, others argue that the mass extinction hasn't begun yet.

Robert Cowie, a research professor at the University of Hawaii, told Live Science that, strictly speaking, you can't declare a mass extinction until it's actually happened — once 75% of species are gone.

A 2022 study led by Cowie and published in the journal Biological Reviews estimated that up to 13% of known species have gone extinct since 1500 — well below the 75% mass extinction threshold.

"It hasn't happened yet," he said.

Some researchers have estimated that we'll reach the 75% threshold within 10,000 years, while other studies have concluded that we could be at this grim milestone in just a few centuries — with the potential for an even shorter time frame if things get worse.

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